1. Field of the Invention
The invention relates generally to systems and methods for creating steerable lateral subterranean tunnels and for monitoring formation of tunnels in real-time at surface.
2. Description of the Related Art
Sidetracking operations create lateral tunnels that extend outwardly from a central wellbore, which is typically substantially vertically-oriented, but might also be horizontally-oriented or inclined. A number of tools and techniques can be used to create lateral tunnels. Included among these tools and techniques are devices that inject acid into the wellbore and surrounding formation in order to dissolve rock. Devices of this type are used, for example, in the StimTunnel™ targeted acid placement service which is available commercially from Baker Hughes Incorporated of Houston, Tex. These acid stimulation devices typically use a bottom hole assembly with a pivotable wand with a nozzle through which acid is dispensed under high pressure. The acid helps dissolve portions of the formation around the nozzle. The wand is typically provided with one or more knuckle joints that help angle the nozzle in a desired direction. Features of this type of tool are discussed in U.S. Patent Publication No. 2008/0271925 (“Acid Tunneling Bottom Hole Assembly”) by Misselbrook et al. [the '925 reference]. The '925 reference is herein incorporated by reference.